Rotary piston pump with single chamber



Dec. 13, 1966 A. J. JAcoBs ROTARY PISTON PUMP WITH SINGLE CHAMBER Filed March 16, 1964 6 Sheets-Sheet 1 Fig. l

A/berf J Jacobs INVIFNTOR.

Dec. 13, 1966 A. J. JACOBS 3,291,63

ROTARY PISTON PUMP WITH SINGLE CHAMBER Filed March 16, 1964 e sheets-sheet 2 Fig. 2

Alberf J Jacobs INVENTOK.

Dec. 13, 1966 A. J. JACOBS 3,29

ROTARY PISTON PUMP WITH SINGLE CHAMBER Filed March 16, 1964 6 Sheets-Sheet 5 A/berf J Jacobs IN VENTOR.

Dec. 13, 1966 A. J. JACOBS 3,291,063

ROTARY PISTON PUMP WITH SINGLE CHAMBER Filed March 16, 1964 6 Sheets-Sheet 4 A/berf J Jacobs INVENTOR.

Dec. 13, 1966 A. J. JACOBS M ROTARY PISTON PUMP WITH SINGLE CHAMBER Filed March 16, 1964 6 Sheets-Shee 5 Albert J Jacabs INVEN TOR.

Dec. 13, 1966 A. J. JACOBS 3,

ROTARY PISTON PUMP WITH SINGLE CHAMBER Filed March 16, 1964 6 Sheets-Sheet 6 lberf J Jacobs IN V EN TOR.

United States Patent 3,291,063 ROTARY PISTON PUMP WITH SINGLE CHAMBER Albert J. Jacobs, Calgary, Alberta, Canada, assignor to Edward J. Carline, Edmonton, Alberta, Canada Filed Mar. 16, 1964, Ser. No. 352,205 31 Claims. (Cl. 103-132) This invention comprises a novel and useful rotary piston pump with single chamber and more particularly pertains to a device of the expansible chamber type in which a ring-type piston has a gyratory or translational movement about the circumference of an annular chamher while maintaining tangency with the concave external periphery and the convex internal periphery of that chamber and thus divides the latter into a pair of radially outer and inner working chambers.

The fundamental purpose of this invention is to provide an apparatus of the positive displacement expansible chamber type which shall be well adapted to function, with the requisite minor changes as to accessories and ancillary equipment, as a pump, fluid motor, internal combustion engine and the like and wherein the reciprocating masses and their inherent disadvantages as found in common types of apparatus are replaced largely by continuously rotating or translationally moving masses.

It is therefore the primary purpose of this invention to provide an expansible chamber device which shall be compact, capable of operating under very high internal pressures and temperatures, shall eliminate the inertia reversals of reciprocating masses by replacing them with uni-directional continuously translationally moving masses.

A further object of the invention is to provide a highly efficient pump of the type having a stator with an annular chamber therein and a stationary core disposed centrally of the chamber together with a ring piston mounted between the core and stator and dividing the space therebetween into radially spaced outer and inner working chambers and with the ring piston being so mounted and controlled as to cause it to move with a gyratory or orbital movement which is purely translational while maintaining tangency upon its outer surface with the stator and upon its inner surface with the core.

Still another purpose of the invention is to provide an apparatus in conformance with the foregoing objects having inner and outer partition blade assemblies for sealing and providing abutments between the rotary piston and the core and stator respectively of the inner and outer working chambers.

Another important object of the invention is to provide an apparatus in conformance with the foregoing objects having a simplified and highly effective construction for effecting the introduction of a fluid into the inner and outer working chambers and the discharge of fluid therefrom in properly timed relation during the cyclic operation of the device.

An additional object of the invention is to provide an apparatus according to the preceding objects which shall include a stabilizing or synchronizing means for positively connecting the ring piston with the stator and limiting and confining the ring piston to a purely translational movement during its gyratory travel within the annular chamber of the stator,

Still another and more specific purpose of the invention is to provide a highly eflicient fluid pressure sealing means between the gyratory piston element and the walls of the inner and outer working chambers during the translational movement of the piston.

A further very important object of the invention is to provide a greatly simplified but a highly eflicient and durable connecting means secured to the stator and piston for rigidifying and strengthening the latter to withstand 3,291,053 Patented Dec. 13, 1966 extremely high working pressures and also to confine the piston to purely translational movement in its working chambers.

Another object of the invention is to provide an expansible chamber device wherein a ring-type piston moves with a purely translatory movement within concentric annular outer and inner working chambers and wherein the Working chambers are of different widths thereby enabling a larger proportion of the total volume of the device to be occupied by the working chambers and enabling a better control of the relative volumes and working pressures of the chambers to the end that the operating pressures and pulsations of the device may be balanced.

These together with other objects and advantages which will become subsequently apparent reside in the details of construction and operation as more fully hereinafter described and claimed, reference being had to the accompanying drawings forming a part hereof, wherein like numerals refer to like parts throughout, and in which:

FIGURE 1 is a top plan view of a suitable embodiment of an apparatus incorporating therein the principles of this invention and being of the single expansible cham ber unit type;

FIGURE 2 is a view taken upon an enlarged scale in vertical central longitudinal section substantially upon the plane indicated by the section line 22 of FIGURE 1;

FIGURE 3 is a view in vertical transverse section taken substantially upon the plane indicated by the section line 3-3 of FIGURE 2;

FIGURE 4 is a detail view in vertical transverse section taken substantially upon the plane indicated by the section line 44 of FIGURE 2 and showing the stabilizing or synchronizing means of the invention;

FIGURE 5 is a fragmentary view in perspective of a portion of the ring piston and the inner and outer partitioning blade assemblies therefor;

FIGURE 6 is a detail view in vertical transverse section taken upon an enlarged scale substantially upon the plane indicated by the section line 66 of FIGURE 3 and showing the valve arrangement within the outer partitioning blade assembly;

FIGURE 7 is an exploded perspective view of the component of the inner partitioning blade assembly;

FIGURE 8 is an exploded perspective view of certain elements including the sealing shoe of the outer partitioning blade assembly;

FIGURES 912 are diagrammatic views of the cycle of movement of the ring piston at successive intervals of its travel;

FIGURE 13 is a central, vertical longitudinal section through a modification of the invention;

FIGURE 14 is an elevational view of the apparatus of FIGURE 13 but with the drive shaft and an end wall removed;

FIGURES 15 and 16 are plan views taken in horizontal section substantially upon the planes indicated by the section lines 15--15 and 1616 respectively of FIGURE 14;

FIGURE 17 is a detail view upon an enlarged scale of the pressure compensating sealing and wear plate of FIGURE 2;

FIGURE 18 is an enlarged detail view of forms of the piston sealing means of FIGURE 14;

FIGURE 19 is an exploded perspective view of sealing blades of the inner partitioning blade assembly; and

FIGURE 20 is a detail view in horizontal section of a pressure compensating component of the inner partitioning blade, being taken substantially upon the plane indicated by the section line 2020 of FIGURE 19; and

FIGURE 21 is a detail view of a modified construction which may be employed with either form of the In the accompanying drawings, the numeral designates generally a rotary pump or compressor incorporating therein the principles of this invention. However, although the device 10 has been described as a pump or compressor, it is inherently an expansible chamber device of the positive displacement type and incorporating therein the principles of this invention as disclosed hereinafter, is equally capable of use as a fluid motor, an engine or other device with appropriate well understood changes necessitated in the structure and in the accessories and equipment pertaining to the particular use of the device.

Referring especially to FIGURE 2 it will be observed that the expansible chamber device 10 comprises a stator and a rotor. The stator component, as shown best in FIGURE 2, consists of a cylindrical casing or rim 12 open at its opposite ends and which conveniently may be provided as shown in FIGURE 3 with a flanged base or support structure 14 by which the device is supported or mounted in any suitable environment. The open ends of the casing 12 are removably closed by a pair of end plates or end walls as at 16 and 18, through the agency of bolts or other fasteners 20. Central openings as at 22 and 24 are provided in the end walls 16 and 18 for the reception of ball bearing assemblies 26 by means of which a drive shaft 28 is journaled for rotation centrally of the stator and the central chamber 30 which is enclosed by the rim 12 and the end walls 16 and 18.

It will be observed that one end of the shaft is completely housed within the stator, it being enclosed by a closure cap 31 secured as by bolts 32 to the end wall 16, while the other end of the shaft projects through the end wall 18 and through an opening 34 in the closure cap 36 which latter is secured as by the fastening bolts 38. It will be particularly noted that the closure caps 31 and 36 engage against the bearing assemblies 26 and thereby prevent axial displacement of the shaft 28.

The power shaft 28 includes a pair of diametrical enlargements 40 upon which the bearing assemblies 26 are mounted together with an adjacent pair of eccentric portions or supports 42, upon which bearing bushings 44 are journaled and which are disposed in the ring piston indicated generally by the numeral 50. It will be further noted that between the eccentric portions or discs 42 the shaft is provided with concentric members in the form of drums 46 having a cam groove 48 therebetween and which last-mentioned members comprise a core journal which by means of a bushing 52 rotatably journals a cylindrical core 54 which is disposed concentrically with respect to the shaft and the interior of the chamber 30.

The ring piston 58 which comprises the rotor of the apparatus includes a pair of side plates or support members 56 and 58 which receive therein the bushings 44 previously mentioned and by which they are each journaled upon the eccentric portions 42 of the shaft. Upon their opposed annular faces the plates have circumferentially extending grooves 60 in which is received the cylindrical sleeve or ring 62 which constitutes the piston element.

From FIGURE 2 it will be observed that the two support plates 56 and 58 slidingly embrace the core 54 therebetween with the member 62 being disposed in an embracing relation about the core upon its inner surface while its outer surface at a 180 opposite position is in tangent contact with the inner surface of the stator rib 64.

The stator rim or casing 12 has the circumferentially extending medially disposed and radially inwardly projecting ring or rib 64 which projects into the space between the two support plates 56 and 58 of the ring piston 50. It will now beobserved that the piston which thus embraces the core 54 and contacts the rib 64 with its ring or sleeve 62 defines a pair of radially spaced outer and inner working chambers 66 and 68 as more clearly seen in FIGURE 3, with the piston ring member 62 being at all times tangent with the cylindrical internal peripheral surface of the rib 64 and the cylindrical external surface of the core 54.

It will be further observed from a consideration of FIGURES 3 and 4, that the core 54 is provided with a plurality of circumferentially spaced axially extending bores or passages 70 therethrough. Extending through each of these passages is a tension member in the form of a bolt 72 whose opposite ends are fixedly secured to the plates 56 and 58 and each such tension member is provided with a spacer sleeve 74 thereon. Each spacer sleeve has a roller 75 journaled thereon which is movably received in and rolls about the internal surface of the corresponding bore 70. The spacer sleeve opposite ends are compressibly engaged by the plates 56 and 58 to thereby retain the latter in properly spaced relation.

The arrangement is such that the spacers and bolts 74 and 72 thus fixedly secure the two side plates 56 and 58 of the rotary piston ring in a fixed spaced relation thereby rigidifying and strengthening the latter against distortion and enabling the rotary piston to thus slidably embrace the rotor and the rib 54 and 64 respectively, therebetween, while preventing the core 54 from rotating.

Stabilizer and piston control means A stabilizing and synchronizing means is provided for maintaining the ring piston in a constant attitude with respect to the stator for imparting a gyratory or translational motion to the ring piston about the core while maintaining the ring piston in parallel positions during such travel. For this purpose, the stabilizing or piston motion control means shown in FIGURES 2 and 4 is provided. This means includes a pair of complementary cooperating members comprising an outer member consisting of an internal gear and an inner member comprising an external ring gear 82 cooperating therewith. As will be apparent from FIGURE 2, the outer member or internal ring gear 80 is generally L-shaped in cross section and is secured as by fasteners 84 to the end wall 16 of the casing of the stator. The outer ring gear 80 includes a plurality of semi-cylindrical pockets 86 with which cooperate teeth 88 provided upon the convex external cylindrical surface of the inner or external ring gear member 82. The latter is secured as by the previously mentioned tension members or fasteners 72 to the end plate 56 of the ring piston 50 for travel therewith. It will be observed that there is provided one such tooth 88 of the external ring gear member for each of the pockets 86 on the internal ring gear member so that each tooth is freely slidable and movable within the pocket during the gyratory movement of the external ring gear 82. Thus, the cooperating engagement of the teeth and pockets on the two ring gear members maintains the ring piston in a constant attitude or a series of parallel positions during its orbital translational travel.

The gearing assembly which effects the translatory movement of the piston 50 may also be effectively used as a means to lubricate and cool the device. Thus, as more clearly seen in FIGURES 2 and 4, an axial bore 81 is provided in the shaft 28 which is closed by a plug 83. An inlet passage connects this bore, through the members 42, 44 with a pocket between the teeth of the external ring 82. Consequently, during the operation of the ring gears 80, 82, lubricant will be pumped into the bore 81. From thence, through passages 87 and 89 the lubricant lubricates the bushings 52 and 44 also cooling the associated parts.

Pressure compensating sealing plate Attention is now directed to FIGURES 2 and 17 for a disclosure of a pressure actuated compensating sealing plate construction constituting an important feature of this form of the invention. The inner annular face of the piston support plate 58 has a circumferential groove or channel 139 of Lshaped cross-section in which is received a sealing plate 141, in the form of a ring of corresponding cross-sections. A dowel pin 143, FIGURE 2, prevents rotation of the plate 141 in its channel. The plate 141 has a planar face comprising a pressure surface 145 which is in continuous sliding and sealing engagement with the adjacent face of the core 54.

Pressure is applied to the rear of the plate 141 by means of intersecting bores 147 and 149 which admit fluid under pressure from the inner working chamber 68 to the bottom of the channel 139. Additional sealing means in the form of O-rings 151 and 153 provide a fluid tight seal for the plate 141 in its channel 139.

It will be noted that the upper portion of the channel 139 intersects the piston slot 60 and that the tapered upper portion of the sealing plate 141 engages the piston sleeve 62.

Partitioning blade assemblies The apparatus as disclosed also includes radially spaced outer and inner partitioning blade assemblies indicated generally by the numerals 100 and 102 as shown in FIG- URES 3 and 5.

For this purpose, the medial internal rib 64 of the stator casing 12 is provided with a radially extending and axially disposed slot 104 therein. A pair of filler blocks 106 and 108 are secured to the inner surface of the stator 12 and to the adjacent surfaces in shouldered recesses of the casing end plates 18 and 16 respectively to close the ends of the slot 104 in the casing 12. Suitable dowel pins 105 and fasteners 107 may be provided for appropriately positioning and retaining the filler blocks 106 and 108 in place.

The outer partitioning blade assembly 100 comprises a generally rectangular, hollow, box-like body 101 which is slidably received in the slot 104 between the ends of the filler blocks 106 and 108 and extends between the radially outer ends of the ring piston side plates 56 and 58 as shown in FIGURE 2, suitable sealing O-rings 110 being provided in circumferentially extending channels on these plates to engage against the medial rib 64 and the outer partitioning blade assembly 100.

As will be noted from FIGURES 2, 3 and 6, compression springs 112 received in the slots 104, bear against the bottom walls of the cups or sleeves 114 each of which is slidably received in a bore 116, terminated at the bottom wall 118 of body 101 of the outer partitioning blade. The lower ends of these sleeves are provided with spherical sockets as at 120 which engage against the ball valves 122, the latter cooperating with valve seats and ports 124 extending through the bottom wall 118 of the partitioning blade. A shoe 126 is detachably secured as by fastening screws 128 to the bottom wall 118. As will be noted from FIGURE 8, the shoe 126 is of a semicylindrical configuration having a lower concave surface including an edge surface 130 which is of the same radius as that of the exterior surface of the ring piston member 62 to have a close fit and engagement therewith. The bottom concave surface of the partitioning blade body 101 is further recessed to provide a chamber or recess 131 which constitutes an exhaust collection chamber communicating continuously with the inner working chamber 68 through the exhaust ports 180, FIGURE 5, in the piston element 62. A pair of bores or passage means 132 extend through the shoe 126 communicating with the valve seats 124 controlled by the valves 122 as will be apparent from FIGURE 6. A pair of semi-cylindrical recesses 134 are likewise formed in the shoe 126 to receive therein retainer blocks 136. These blocks are apertured as at 138 for the reception of the fasteners 128 which extend through these blocks and into internally threaded bores 142 in the bottom wall 118 of the block 101 and may be riveted over upon their inner ends as at 140.

The arrangement is such that the shoe establishes a fluid tight seal at its rectangular edges along the edge surface with the adjacent surfaces of the ring piston member 62, with the springs 112 urging the outer partition blade into resilient engagement with the ring piston. Consequently, as the piston performs its gyratory or translational movement, the outer partition assembly 100 maintaining a sliding contact therewith is radially reciprocated in its slot 104.

The inner partitioning blade assembly 102 is of a somewhat simpler construction. For this purpose the core 54 is provided with a radially disposed axially extending slot therein and the inner partitioning blade 152 is slidably received in the slot with its upper edge being provided with a lip 154 which bears against the inner convex surface of the ring piston member 62. As will be noted from FIGURE 7, the plate-like member 152 has its extremities projected downwardly as at 156 leaving a central notch or recess 158 therebetween. Referring now to FIGURE 2 it will be observed that the bottom of the slot in the core 54 has a correspondingly shaped upward projecting portion 159 against which the portions 156 and 158 may seat.

A lifter rod 160 is slidably received in a bore 162 opening through the portion 159 of the core and also through the core hub bushing 52. A bushing 165 is press fitted into a counterbore 167 of the bore 162 and is removable by the use of a suitable knock-out tool through a bore 169, see FIGURE 2, opening into the bottom of the slot 150. An O-ring seal in the bushing 165 establishes a fluid tight seal for the bore 162 preventing the escape of working fluid from the inner chamber 68 therethrough. An arcuately shaped foot 164, see FIGURES 5 and 7, is received in the same groove 48 of the shaft 28 and engages the lower end of the lifter rod 160 to effect upward movement of the latter in response to rotation of the shaft 28. By properly correlating the shape of the cam groove 48 with the position of the ring piston, it is evident that the inner partitioning blade can be raised and maintained in a substantially fluid tight sliding engagement wth the inner concave surface of the ring piston member 62 during the gyratory movement of the latter.

Referring to FIGURE 7, the plate-like lower partitioning blade 152 is provided with a pair of channels 163 upon the high pressure side. These conduct working fluid from the inner working chamber 68 to the underside of the blade 152 to assist in urging the blade radially outwardly into a pressured sealing engagement with the inner surface of the piston element 62. It should be noted that this sealing pressure is proportional to the working pressure in the inner chamber.

In this manner, the outer and inner partitioning members provide closed abutments for the outer and inner working chambers respectively of the device.

Means are provided for effecting the inlet of fluid into and the exhaust of fluid from the outer and inner working chambers of the device. For this purpose, as shown in FIGURE 3, there is provided a fluid inlet passage 170 in the casing 12 together with an exhaust passage 172, these passages being disposed on opposite sides of the outer partitioning blade assembly. It will be observed that the inlet passage 170 is open at all times to the interior of the casing section 12 and thus to the outer and inner working chambers 66 and 68. However, the exhaust passage 172 is provided with a control valve 174 which is engaged by a valve follower 176 under the action of a spring 178 to yieldingly urge the valve to closed position until it is opened by the compression of the fluid within the chamber 66. The outer partitioning blade assembly, however, provides an exhaust valve assembly for the inner working chamber 68. For this purpose,

there is provided an exhaust port or ports 180, see FIGURE 5, in the ring piston member 62 which are registrable with the previously mentioned recessed chamber 131 and the exhaust ports 132 of the shoe 126, so that the fluid under pressure in the chamber 68 will be discharged therefrom. A further port 182 is provided in the member 62 which establishes at all times communication between the outer chamber 66 and the inner chamber 68.

Consequently, during operation of the device it will be evident that fluid is supplied to and discharged from the two working chambers thereof in a cyclic manner.

The diagrammatic views of FIGURES 9-12 disclose the manner in which the gyratory movement of the ring piston element 62 by its tangential contact with the core and with the inner cylindrical wall of the stator moves progressively thereabout causing the circumferential displacement of the inner and outer working chambers from their inlet at the right side of the outer partitioning blade assembly, about their circumference and to the exhaust thereof at the left side of the partitioning blade assembly.

Embodiment of FIGURES 13-16 and 1820 Attention is now directed to FIGURES 1320 showing a simplified modification possessing a single expansible chamber unit having a C-shaped ring or sleeve comprising the rim of the ring piston.

The stator component consists of a cylindrical rim 230 whose open ends are removably closed by a pair of identical end plates or end walls 232 by means of fasteners 236. Mounted in axial openings 238 in the end walls 232 are bearing assemblies 240, retained by hearing closure caps or plates 242 by the fastening bolts 244. The power shaft 250 is journalled in these hearings, having its ends extending through the bearing caps for applying power to or taking power from the device, suitable seals 252 being provided in the plates 242.

A pair of eccentric members 254 are integrally formed upon the shaft 250 and a cylindrical drum-like member core journal 256 is disposed between the eccentrics 254. The eccentrics 254 comprise eccentric supports upon which are journalled by roller bearing assemblies 258 a pair of support plates 260 and 261 comprising the side walls or end plates of a ring piston indicated in its entirety by the numeral 262.

The ring piston 262 consists of a C-shaped cylindrical sleeve 264 constituting an exhaust port and an inlet port for the inner chamber, together with the pair of piston side plates 260 and 261, each of which has a circumferential channel or groove 268 in which the edges of the sleeve 264 are seated.

Mounted upon the core journal 256 is a bushing 257 which carries a cylindrical core 270 which is concentric with the axis of the shaft 250.

In order to rigidify and strengthen the ring piston 262 and enable it to operate under extremely high working pressures, inner and outer sets of circumferentially spaced tension bolts 272 and 274 are provided which extend between and are secured to the piston side plates 261 and also extend through the core 270 and the stator 230 respectively. To this end, axial bores 276 extend through the core, receiving therethrough the bolts 272 while a radially inwardly projecting medial rib 278 in the stator rim 230 has a series of axial bores 280 through which the bolts 274 are disposed.

The outer bolts 274 have spacer sleeves 275 therein which are compressively clamped between the piston side plates 260, 261 and rollers 277 on the spacer sleeves 275 revolve about the peripheral surface of the stator bores 280 thereby confining the piston 262 to a purely translational movement about the core 270 and within the stator 230.

As in the preceding embodiment the piston rim 264 divides the annular space between the core 270 and the stator 230 into concentric inner and outer working cham- 8 bers 282 and 284 respectively. Since the piston rim 264 is at all times tangent to the stator and core the working chamber in turn revolves thereabout.

A partitioning blade assembly indicated generally at 285, see FIGURES 14, 19 and 20, extends through the ring opening between the core and stator and across the inner and outer working chamber, having its ends received in corresponding radial slots 286 and 288 in the core and stator respectively.

As shown in FIGURE 19, the blade assembly consists of two relatively movable components, comprising blocklike bodies 290 and 292, body 290 being rigidly mounted by the core 270.

It will be observed from FIGURE 13 that the piston side plate 261 has a centrally recessed wall portion 293 within which the core 270 is received, the channel 268 bounding this recessed portion. The inner and outer chambers are thus of different widths or axial extents and therefore the blade 285 is correspondingly shaped as shown in FIGURE 19.

One radial edge of the body is cut away at 294 leaving a lower projecting portion 296 and a radial groove, channel or guideway slot 298 is formed therein. The upper edge of the block 290 at the bottom of the cut-away portion has a transversely rounded or convex shoulder surface 300. At its lower end the portion 296 has a transverse passage or slot 302 therethrough.

Radially slidable in the slot 298 of the body 290 is the member 292. This member has an upper portion 304 substantially filling the slot 298 and a lower portion 306 co-extensive with the radial edge of the portion 296. The portion 306 has an upper edge 308 which is transversely convex and is projected radially upwardly thereabove as set forth hereinafter. The body 292 has vertically extending fluid channels 310 and 312 upon the radial edges of its portion 304 and 306 respectively and additional vertical channels 314 and 316 on its high pressure side with which communicate cross bores 318 and 320 respectively, as shown in FIGURE 20.

In operation, the portions 296 and 306 lie in the recess 293 with the sealing surface 308 engaging the shoulder of the recess 293 and the piston rim 264. Pressure from the inner working chamber 282 on the high pressure side of the blade enters the channels 310, 312, 314, 316 and the bores 318, 320 thus engaging all surfaces of the body 292. In addition the pressure differential on the vertically spaced areas urges the body 292 radially outward into sealing contact with the stator inner wall and the ring piston.

In this embodiment, both inner and outer working chambers discharge through the same exhaust passage 324 in the stator rim 230 to any suitable delivery conduit system. Similarly both chambers intake fluid from a single intake conduit 326.

The conduits 324 and 326 enter the stator 230 on opposite sides of the partitioning blade 285 communicating with the outer chamber. Through the port or opening 269 of the piston rim 264, the inner chamber communicates with the outer chamber for intake and exhaust. The piston rim 264 itself operates as a valve to control flow through the two intake and two exhaust ports.

To effect this purpose a pair of sealing elements are provided comprising elements 328 and 330 disposed on the ring piston rim and core and respectively engaging the stator rim 230 and the ring piston rim 264. Referring to FIGURE 18, it will be seen that the elements 328 and 330 are identical, having bases 332 and 334 by which they are securely seatedin the piston rim and core. These elements have upstanding lips 336 and 338 which during the orbital movement of the piston rim 264 moves slidingly and sealing over the appropriately recessed surfaces 340 and 342 respectively provided in the stator and piston. These last mentioned surfaces are broken or cut-away at 334 and 346 to release the sealing action.

It will be noted that in both forms of the invention the inner and outer worknig chambers are of different widths. In the two illustrated modifications, the inner chamber is of the greater width, and the partitioning blade assemblies are specifically proportioned for this arrangement. Consequently, the volume of one chamber is not limited necessarily by the volume of the other and full advantage can be obtained of utilizing the available dimensions and internal volume of the device for proportioning the respective volumes and working pressures of the two working chambers. For example, their relative volumes and pressures can be varied while maintaining a balancing of their total forces and pressure pulsations.

In FIGURE 21 there is disclosed a modified construction of the ring piston which may be incorporated into either of the embodiments of FIGURES 1-12 or 13-20. For convenience only, it has been illustrated as applied to the C-shaped ring piston 264 of FIGURES 13-20.

When the ring piston moves towards its uppermost point of tangency with the stator or the core, the corresponding working chambers narrow to a Wedge-shaped configuration whose apices :lie at the points of tangency. Owing to the narrow tapering width of the working chambers at the points of tangency, skin friction of the fluid being compressed prevents complete filling of the chambers. This condition is alleviated by the arrangement shown in FIGURE 21 wherein the system of appropriately sized and positioned passages 271 through the ring piston 264 permits the filling of the wedge-shaped portion of either working chamber by fluid from the other.

The foregoing is considered as illustrative only of the principles of the invention. Further, since numerous modifications and changes will readily occur to those skilled in the art, it is not desired to limit the invention to the exact construction and operation shown and described, and accordingly all suitable modifications and equivalents may be resorted to, falling within the scope of the invention as claimed.

What is claimed as new is as follows:

1. An expansible chamber device of the positive displacement rotary piston type comprising a stator including a peripheral wall and a pair of side walls secured thereto and defining therewith a central chamber, a core disposed centrally of said central chamber, a ring piston, means mounting said ring piston in said central chamber for purely translational movement about said core and tangent to both said peripheral wall and said core and dividing said central chamber into radially spaced outer and inner working chambers of different axial dimensions respectively disposed between said ring piston and said peripheral wall and core, stabilizing means connected to said ring piston and stator and restraining said piston to translational movement in said central chamber about said core, intake means and exhaust means respectively supplying fluid to and discharging fluid from each of said outer and inner working chambers and partitioning means slidably mounted by the core and the stator for dividing the working chambers between the intake and exhaus t means.

2. The combination of claim 1 wherein said stator has an intermediately disposed radially inwardly projecting circumferentially extending rib, said ring piston including side walls slidably embracing the opposite sides of both said rib and core.

3. An expansible chamber device of the positive displacement rotary piston type comprising a stator including a cylindrical peripheral wall and a pair of side walls secured thereto and defining therewith a central chamber, a cylindrical core disposed centrally of said central chamber, a ring piston, means mounting said ring piston in said central chamber for purely translational movement about said core and tangent to both said peripheral wall and said core and dividing said central chamber into radially spaced outer and inner working chambers respectively disposed between said ring piston and said peripheral wall and core, stabilizing means connected to said ring piston and stator and restraining said piston to translational movement in said central chamber about said core, intake means and exhaust means respectively supplying fluid to and discharging fluid from each of said outer and inner working chambers, said ring piston comprising a pair of parallel circular support plates, com plementary circumferential channels on adjacent faces of said support plates, and a sleeve secured to said support plates and having its peripheral edges seated in said channels.

4. The combination of claim 3 including a plurality of tension members each having its ends secured to said support plates and rigidly connecting the latter.

5. The combination of claim 4 wherein said core includes a plurality of axial bores therethrough, said tension members being each received in and being freely movable in one of said bores.

6. The combination of claim 5 including spacer sleeves each surrounding a tension member and compressively engaged by said support plates.

7. An expansible chamber device of the positive displacement rotary piston type comprising a stator including a cylindrical peripheral wall and a pair of side walls secured thereto and defining therewith a central chamber, a cylindrical core disposed centrally of said central chamber, a ring piston, means mounting said ring piston in said central chamber for purely translational movement about said core and tangent to both said peripheral wall and said core and dividing said central chamber into radially spaced outer and inner working chambers respectively disposed between said ring piston and said peripheral wall and core, stabilizing means connected to said ring piston and stator and restraining said piston to translational movement in said central chamber about said core, intake means and exhaust means respectively supplying fluid to and discharging fluid from each of said outer and inner working chambers, said ring piston comprising a sleeve surrounding said core and a pair of support plates fixedly secured to and supporting the opposite edges of said sleeve, said support plates slidably embracing said core therebetween and defining said inner working chamber between said support plates, core and sleeve.

8. The combination of claim 7 wherein one of said support plates has a circumferential groove in a face thereof adjacent said core, a sealing ring received in said groove and having a face slidably engaging said core, said ring being movable in said groove towards and from said core, means applying fluid under pressure into said groove and urging said ring against said core.

9. An expansible chamber device of the positive displacement rotary piston type comprising a stator including a cylindrical peripheral wall and a pair of side walls secured thereto and defining therewith a central chamber, a cylindrical core disposed centrally of said central chamber, a ring piston, means mounting said ring piston in said central chamber for purely translational movement about said core and tangent to both said peripheral wall and said core and dividing said central chamber into radially spaced outer and inner working chambers respectively disposed between said ring piston and said peripheral wall and core, stabilizing means connected to said ring piston and stator and restraining said piston to translational movement in said central chamber about said core, intake means and exhaust means respectively supplying fluid to and discharging fluid from each of said outer and inner working chambers, said ring piston comprising a sleeve surrounding said core and a pair of support plates fixedly secured to and supporting the opposite edges of said sleeve, said support plates slidably embracing said core therebetween and defining said inner working chamber between said support plates, core and sleeve, outer and inner partitioning blade assemblies estabv 1 1 lishing abutments between said piston sleeve and said stator and core respectively.

10. An expansible chamber device of the positive displacement rotary piston type comprising a stator including a cylindrical peripheral wall and a pair of side walls secured thereto and defining therewith a central chamber, a cylindrical core disposed centrally of said central chamber, a ring piston, means mounting said ring piston in said central chamber for purely translational movement about said core and tangent to both said peripheral wall and said core and dividing said central chamber into radially spaced outer and inner working chambers respectively disposed between said ring piston and said peripheral wall and core, stabilizing means connected to said ring piston and stator and restraining said piston to translational movement in said central chamber about said core, intake means and exhaust means respectively supplying fluid to and discharging fluid from each of said outer and inner working chambers, said ring piston comprising a sleeve surrounding said core and a pair of support plates fixedly secured to and supporting the opposite edges of said sleeve, said support plates slidably embracing said core therebetween and defining said inner working chamber between said support plates, core and sleeve, outer and inner partitioning blade assemblies establishing abutments between said piston sleeve and said stator and core respectively, said outer partitioning blade assembly including a slot in the inner surface of said stator, a blade body slidably'received in said slot, a shoe movably mounted on said blade body and engaging said piston sleeve with a fluid tight engagement.

11; The combination of claim wherein said inner partitioning blade assembly includes a slot in said core, an inner blade received in said core slot, a cam groove in said core, a guide bore in said core communicating with said cam groove, a foot riding in said cam groove, a lift rod slidable in said guide bore and engaging said foot and said inner blade and operable to retain the latter in sealing engagement with said piston sleeve and core and constituting an abutment for said inner working chamber.

12. The combination of claim 11 wherein said intake means and exhaust means communicate with said working chambers on opposite sides of said outer and inner partitioning blade assemblies.

13. The combination of claim 1 wherein said partition means includes outer and inner partitioning blade assemblies constituting abutments disposed respectively in said outer and inner working chambers and carried respectively by said stator and core and both having a sliding fluid tight engagement with said ring piston on opposite radial sides thereof.

14. An expansible chamber device of the positive displacement rotary piston type comprising a stator including a cylindrical peripheral wall and a pair of sidewalls secured thereto and defining therewith a central chamber, a cylindrical core disposed centrally of said central chamber, a ring piston, means mounting said ring piston in said central chamber for purely translational movement about said core and tangent to both said peripheral Wall and said core and dividing said central chamber into radially spaced outer and inner working chambers rsepectively disposed between said ring piston and said peripheral wall and core, stabilizing means connected to said ring piston and stator and restraining said piston to translational movement in said central chamber about said core, intake means' and exhaust means respectively supplyingfluid to and discharging fluid from each of said outer and inner working chambers, outer and inner partitioning blade assemblies constituting abutments disposed respectively in said outer and inner working chambers and carried respectively by said stator and core and both having asliding fluid tight engagement with said ring piston on opposite sides thereof, said outer partitioning blade assembly comprising a blade body slidably mounted in a slot in said stator, a semi-cylindrical socket in said blade body, a shoe oscillatably seated in said socket and having a concave bearing face engaging said ring piston, means retaining said shoe in said socket, exhaust passage means establishing communication from said inner working chamber to said exhaust means through said ring piston, shoe, socket and blade body.

15. An expansible chamber device of the positive displacement rotary piston type comprising a stator including a cylindrical peripheral wall and a pair of side walls secured thereto and defining therewith a central chamber, a cylindrical core disposed centrally of said central chamber, a ring piston, means mounting said ring piston in said central chamber for purely translational movement about said core and tangent to both said peripheral wall and said core and dividing said central chamber into radially spaced outer and inner working chambers respectively disposed between said ring piston and said peripheral wall and core, stabilizing means connected to said ring piston and stator and restraining said piston to translational movement in said central chamber about said core, intake means and exhaust means respectively supplying fluid to and discharging fluid from each of said outer and inner working chambers, said ring piston comprising a cylindrical rim supported upon a pair of support plates, said stator having a radially inwardly projecting rib, said support plates slidably embracing said core and rib, radially spaced inner and outer sets of tensioning members each fixedly secured to said support plates, axial bores in said core and rib through each of which extends one of said tensioning members.

16. The combination of claim 15'Wherein said inner set of tensioning members secures said core against rotation.

17. The combination of claim 15 wherein each of said outer set of tensioning members has a spacer sleeve thereon disposed in the associated bore and compressively engaged by said support plates.

18. The combination of claim 17 including rollers journalled upon said spacer sleeves and revolvably engaging the wall of the associated bores, said outer set of tensioning members, spacer sleeves and rollers comprising said stabilizing means.

19. The combination of claim 9 wherein said piston sleeve has an opening extending thereacross said partitioning blade assemblies extending through said opening, said opening and opposite sides of said blade assemblies defining intake and exhaust ports for said inner working chamber.

20. The combination of claim 1 wherein said inner working chamber is of greater axial width than said outer working chamber.

21. The combination of claim 1 wherein said partitioning means comprises a single radially extending blade and a laterally extending body slidably mounted upon said blade for relative radial movement, said ring piston comprising a C-shaped cylindrical sleeve with an opening thereacross through which said blade extends.

22. The combination of claim 21 wherein said blade is slidably received in radial slots in said stator and core, means applying fluid under pressure into said core slot beneath said bladeand said laterally extending body and urging the blade and body into sealing engagement with said stator and piston.

23. The combination of claim 22 wherein said pressure applying means includes differential areas on said blade and body.

24. The combination of claim 1 wherein said partitioning means comprising a single radially extending blade and a laterally extending body slidably mounted upon said blade for relative radial movement, said ring piston comprising a C-shaped cylindrical sleeve with an opening thereacross through which said blade extends.

25. The combination of claim 1 wherein said ring piston adjacent said exhaust means and on the high pressure side of said partitioning means has passages therethrough establishing limited communication between said inner and outer chamber.

26. The combination of claim 1 wherein said stabilizing means comprises engaging external and internal gears each fixedly secured to one of said stator and rotor, said gears having the same number of teeth.

2'7. The combination of claim 26 including lubricant passages connecting one pair of cooperating teeth on said external and internal gears with moving parts of said devices for lubricating and cooling the latter.

28. An expansible chamber device comprising, a rotor having a rotational axis, a stator rotatably mounting said rotor about the rotational axis, a piston assembly, means connected to the rotor for mounting the piston assembly about an eccentric axis offset from the rotational axis, said piston assembly including fluid tight enclosure means in operative engagement with the rotor and the stator for establishing an annular chamber about the rotor and an annular piston element carried by the enclosure means within the chamber in tangential contact with the rotor and the stator forming radially outer and inner working spaces of different volumes, stabilizing means mounted by the piston assembly and engageable with the stator for restraining movement of the piston assembly in response to rotation of the eccentric axis about the rotational axis, partition means mounted by the stator and the rotor for radial displacement in response to said restrained movement of the piston assembly and flow conducting passage means extending through the stator in fluid communication with the radially outer working space on opposite sides of the partition means.

29. The combination of claim 28 wherein said enclosure means includes a pair of plate members having annular channels receiving the annular piston element in concentric relation to the eccentric axis, said plate members having confronting surfaces axially spaced from each other by different amounts on opposite radial sides of the piston element.

30. The combination of claim 29 wherein said partition means comprises, blade means slidably mounted by the rotor for radial displacement within a slot formed in the stator, and fluid pressure means for urging the blade means into sealing contact with one of the plate members of the piston assembly.

31. The combination of claim 28 wherein said partition means comprises, blade means slidably mounted by the rotor for radial displacement within a slot formed in the stator, and fluid pressure means for urging the blade means into sealing contact with the piston assembly.

References Cited by the Examiner UNITED STATES PATENTS 940,817 11/1909 McLean et al 230-146 1,462,848 7/1923 Berry 1238 2,561,280 7/1951 Karnpf 9156 2,649,053 8/1953 Stratveit 103131 2,966,898 1/1961 Rydberg et al 1238 3,125,031 3/1964 Rydberg et al 103132 3,125,032 3/1964 Smith 103-131 3,148,626 9/1964 Smith 103131 MARK NEWMAN, Primary Examiner.

WILBUR I. GOODLIN, Examiner. 

1. AN EXPANSIBLE CHAMBER DEVICE OF THE POSITIVE DISPLACEMENT ROTARY PISTON TYPE COMPRISING A STATOR INCLUDING A PERIPHERAL WALL AND A PAIR OF SIDE WALLS SECURED THERETO AND DEFINING THEREWITH A CENTRAL CHAMBER, A CORE DISPOSED CENTRALLY OF SAID CENTRAL CHAMBER, A RING PISTON, MEANS MOUNTING SAID RING PISTON IN SAID CENTRAL CHAMBER FOR PURELY TRANSLATIONAL MOVEMENT ABOUT SAID CORE AND TANGENT TO BOTH SAID PERIPHERY WALL AND SAID CORE AND DIVIDING SAID CENTRAL CHAMBER INTO RADIALLY SPACED OUTER AND INNER WORKING CHAMBERS OF DIFFERENT AXIAL DIMENSIONS RESPECTIVELY DISPOSED BETWEEN SAID RING PISTON AND SAID PERIPHERAL WALL AND CORE, STABILIZING MEANS CONNECTED TO SAID RING PISTON AND STATOR AND RESTRAINING SAID PISTON TO TRANSLATIONAL MOVEMENT IN SAID CENTRAL CHAMBER ABOUT SAID CORE, INTAKE MEANS AND EXHAUST MEANS RESPECTIVELY SUPPLYING FLUID TO AND DISCHARGING FLUID FROM EACH OF SAID OUTER AND INNER WORKING CHAMBERS AND PARTITIONS MEANS SLIDABLY MOUNTED BY THE CORE AND THE STATOR FOR DIVIDING THE WORKING CHAMBERS BETWEEN THE INTAKE AND EXHAUST MEANS. 